<!DOCTYPE html>
<html>
<body>
    <h1>JavaScript 类方法</h1>
    <p>将参数传递给 "age()" 方法。</p>
    <p id="demo"></p>
    <script>
        class Car {
            constructor(name, year) {
                this.name = name;
                this.year = year;
            }
            age(x) {
                return x - this.year;
            }
        }
        let date = new Date();
        let year = date.getFullYear();
        let myCar = new Car("Ford", 2014);
        document.getElementById("demo").innerHTML =
            "My car is " + myCar.age(year) + " years old.";
    </script>
</body>
</html>